Changing Attitudes Vital To Successful Gas Field Automation

It takes more than high tech hardware and sophisticated software to successfully automate remote, widely-separated gas wells, especially under the difficult environmental conditions in Canada. No matter how dedicated the management or how skilled the automation engineers are in planning and implementing such a system, acceptance of automation by field operations personnel is essential to its success! Clearly, without operator support and without internal utilization of the information produced, no system can deliver all the benefits promised. Nothing less than a change of corporate culture is required for field automation to succeed.

Heather Goranson, Manager of Production Automation at Wascana Energy, Inc., Regina, Saskatchewan, and Staff Automation Engineer Ray Knudsen recognized the need to gain operator acceptance if a broad program of field automation were to succeed, and they are beginning to see positive results to actions taken to gain operator acceptance.

"People throughout the company are starting to recognize the capabilities of the system and to rely on the accuracy of information being generated," Goranson said. "One immediately recognizable result is that costs to operate field vehicles have dropped dramatically for reasons directly attributable to the new remote means of obtaining information on the productivity and operating condition of the wells."

Automating Field Operations

Nearly two years ago, Wascana Energy, Inc., one of the largest oil and gas producers in Canada, embarked on a three-year plan to bring the highest economically feasible level of automation to all of the company's gas fields in Saskatchewan and Alberta at an estimated total cost of approximately $30 million Canadian. While substantial progress has been made, it will probably be at least two years before the project is completed.

"Our earliest experience in field automation was in the Willistan Basin in southeastern Saskatchewan, a fairly accessible area producing both oil and gas," Knudsen said. "Pump-off controllers are used on all of the higher producing horizontal wells in this area for pump control, dynamometer analysis, flow measurement, tank level monitoring, water injection facility control, and flowline leak detection."

Since then, two major gas operating areas have been equipped with SCADA (Supervisory Control and Data Acquisition) systems using electronic flow measurement equipment at each wellsite. One SCADA system, implemented in 1996 in northwest Saskatchewan, remotely monitors the performance of some 75 natural gas wells scattered over approximately 2,100 square miles of rugged terrain. The host is located in the community of Pierceland near the Alberta provincial border.

Another area is even more remote in northeastern Alberta. The nearest compressor site is about an hour's drive from Ft. McMurray, where the host file server is located. In addition to electronic flow measurement, most of the wells in this area are equipped with throttling valves, making it possible to remotely control the flow of gas at each well.

Production from the shallow gas operations in these two large areas is on the order of 160 million cubic feet per day. However, the difficulty of maintaining these remote wells can cause productivity to suffer. In winter, snow and cold weather hampers operations, and in summer, heavy undergrowth can make roads all but impassable. However, automation has substantially reduced the number of necessary operator visits to the wellsites.

The wells are equipped with a combination of hardware and software elements including Fisher Controls' ROC312 Remote Operations Controller (ROC) units, Rosemount pressure and temperature transmitters, and various control valves. The ROCs measure gas flowing from the wells and calculate volumes using AGA-3 equations to compensate for temperature and pressure variations. The remote units are also used as controllers, opening and closing valves as necessary. In addition, they provide valuable information about the operating condition of the wells, enabling operators to determine which wells need maintenance and which ones can be left alone.

Communication with the ROC units is maintained by a combination of radio, microwave, and land telephone lines. The SCADA hosts run Wonderware InTouch software as the operator interface, customized to include a dynamic link to the Gensym G2 application. These servers are tied into the company wide area phone network, so production data from the most remote wellsite is available almost instantly to engineers and managers throughout the company.

The Changing Role of the Operator

While some companies have had difficulty convincing their operators that automation is a good idea, Wascana gained the cooperation of its operators at an early stage by involving them in planning the field installations. Working with the automation engineers to explain how things are done in the field, they actually helped design the new system. As a result, the operators took "ownership" of the system; it was "theirs" as opposed to having automation thrust upon them by the company.

"One or two operators are assigned to the automation project in each field," Goranson said, "and they become important resources for us, attending planning meetings and working with engineers to implement the system. The result, we believe, is a more workable product which they have readily accepted because of their involvement in its development."

Automation has also changed the operators' role, making their jobs easier in some ways and enabling them to be more effective in managing the operation and maintenance of the wellsites to which they are assigned. In the gas fields, Wascana operators are very much in control of production, but they no longer need to make regular visits to each site to service chart recorders, because that data is automatically communicated to the SCADA hosts. Using the operator interface, each operator can quickly determine if any wells are malfunctioning and plan corrective action. They can organize their daily activities in the most efficient way. They can even log onto the system from home using laptop computers in order to change production setpoints or shut down a well, if necessary.

Results

"The main tangible benefits expected from oil and gas well automation are increased production volumes and decreased operating costs," Goranson said. "Increased production, estimated between 2 and 30 percent, stems primarily from better well control and improved flow measurement. Operating costs are reduced through: lower power consumption (10-20 percent), fewer downhole failures (15-45 percent), lower surface maintenance and repair costs (5-40 percent), lower driving and vehicle costs (30-85 percent), and reduced costs for overtime and contract labor (35-65 percent)."

According to Knudsen, "The ease of using the ROC units and the host machines makes it possible for operators to essentially run the production system remotely. As a result, every operator can be more efficient. In the past, the first sign of a problem was generally a reduced flow of gas into compressor stations. Operators then had to systematically check wells and pipelines in person to find the malfunction in order to make repairs. Now, when such problems arise, alarms pinpoint the location, saving many hours of searching on a trial and error basis. That alone resulted in vehicle cost savings of 30 to 35 percent in the first six months the system was in operation."

During the winter, freezing of wells with high water-gas ratios has been a fairly common occurrence, but last winter our operators prevented this problem before it could shut down a single well. Utilizing the ROCs to remotely unload the wellbore by alternating gas flow between the production casing and tubing string, freezing was totally eliminated despite one of the coldest winters on record in Saskatchewan. Productivity was maintained throughout the winter by using the ROC units to effectively optimize individual well performance.

The company is also working to improve access to information about the wells. Wascana's wide area phone network is being tied-in with the SCADA host servers to enable engineers at almost any company location to access the operating pressure on a given well. Management personnel, using the same system, will be able to obtain accurate up-to-date information on gas flows and production volumes for use in their projections.

Two other important benefits of field automation are improved safety and protection of the environment. Remote monitoring provides continuous information on the operating condition of wells, which enables operators to identify potential problems, such as valve wear from sand and water in gas areas, and take corrective action before serious damage occurs. In addition, leaks can be detected by system monitors and repaired before the local environment is damaged.

Personal safety for employees has improved in the gas areas for several reasons. First, they have to do less driving under hazardous conditions. With the SCADA system helping to pinpoint developing problems, unnecessary driving has been eliminated. Second, because operators are able to recognize valve wear, repairs can be made in time to prevent potential blow outs.

Conclusion

"There's no question that automation of gas and oil wells pays off," Goranson said. "Financial benefits can be realized through increased production volumes and lower operating costs. However, the speed with which the payback occurs, especially the cost reduction, depends largely on how enthusiastically field operators accept the new system."

In studies conducted by Wascana Energy prior to committing large sums of money to automation, other companies stressed that operational support was vital to the success of any such project. Most companies admitted they had a difficult time convincing operators that automation was a good idea.

However, acceptance of field automation has been excellent at Wascana Energy. This is due in large part to the early involvement of operating personnel in planning and developing field aspects of the automation system. As a result, almost all operating personnel have been wholehearted supporters of the program.